In order to perform management of tires in use, there is known a proposal for mounting a tire management system onto a vehicle, wherein a sensor module is secured to inside of a tire, for measuring a tire status value inclusive of the pressure or temperature of the tire. In this instance, the measured data transmitted from the sensor module is received by a receiver module on the vehicle body side, and the received data is transmitted to a vehicle operation-managing center for managing operation of a plurality of vehicles. According to this proposal, based on the data of the tire management system of each vehicle, if it is judged that there is a possibility of failure of the vehicle, necessary instruction is given from the vehicle operation managing center to the driver so as to prevent occurrence of dangerous state. Reference may be had, for example, to Patent Document 1, Japanese Patent Application Laid-open Publication No. JP 10-104103 A.
In such a tire management system, a data demand signal is transmitted from each receiver module to a corresponding sensor module at a predetermined cycle, and the sensor module performs measurement of the tire status value in accordance with the reception timing of the data demand signal and transmits the measured results to the receiver module, thereby allowing the receiver module to acquire the measured data from the sensor module.
Patent Document 1: JP 10-104103 A